Railway switch operating apparatus



Jan. 19, 1937. w, c. McWHlRTER ET AL 2,067,974

RAILWAY SWITQH OPERATING APPARATUS- Filed Jan. 26, 1935 '5 Sheets-Sheet l INVENTORS lULllzam CMQlU/zz'mer dEdwiI2 CLLL'zfle.

T H5111 A TT ORNE Y 1937. w. c. M WHIRTER ET AL 2,067,974

RAILWAY SWITCH OPERATING APPARATUS 5 Sheets-Shet 2 Filed Jan. 26, 1935 7 I l I 1 mm ATTORNEY BY an dllll ll L 16 Jan. 19, 1937.

w. M WHIRTER ET AL RAILWAY SWITCH OPERATING APPARATUS Filed Jan. 26, 1935 5 Sheets-Sheet 3 I I INVENT RS willz'am GMQLU/zip er and, y Ed amide. I

THEIR ATTORNEY- Jan. 19, 1937. w. c. M WHIRTER ET AL RAILWAY SWITCH OPERATING APPARATUS 5 Shets-Sheet 4 Filed Jan.. 26, 1935 INVENTORS warmer/1910mm and Ed in OLI'ZZZQJ THEIR ATTORNEY Jan. 19, 1937. w. c McWHlRTER ET AL 2,067,974

RAILWAY S WITCH OPERATING APPARATUS 5 Sheets-Sheet 5 Filed Jan. 26, 1935 WSW v P w e S o 0 L Wm m m A N mm wk mu mm H m m ,l 1 w Mm; F J NN 4 i k i\ Q @m @i W? l g R Q Q 5 %m mm m .1 M :5 I I'll. mm

mm.-- mm mm mm WQBQN Q QQ MS RN Patented Jan. 19, 1937 QFFICE RAILWAY SWITCH OPERATING APPARATUS William C. McWhirter and Edwin G. Little, Wilkinsburg, Pa., assignors to The Union Switch & Signal Company, Swissvale, Pa., 3, corporation of Pennsylvania Application January 26, 1935, Serial No. 3,626

19 Claims. (01. 245-240) Our invention relates to railway switch operating apparatus, andparticularly to apparatus including a gear train driven by an electricmotor.

One object of our invention is the provision, in apparatus of the type described, of novel brake mechanism for preventing creeping of the gear train when the motor is deenergized.

Another object of our invention is to provide novel means for protecting the apparatus against starting and stopping shocks.

Other objects of our invention will appear as the description proceeds.

We will describe two forms of apparatus embodying our invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a top plan view showing one form of switch operating apparatus embodying our invention, the cover being removed to better illustrate the construction of the parts. Fig. 2 is a vertical sectional view of the apparatus shown in Fig. 1 taken substantially on the line IIII of Fig. 1. Figs. 3, 4, and 5 are sectional views taken substantially on the lines III-III, IV-IV, and VV, respectively, of Fig. 2. Fig. 6 is a sectional view taken on the line VL-VI of Fig. 5. Figs. 7 and 8 are side and bottom views, respectively, of the brake releasing cam 6| shown in 2. Fig. 9 is a sectional View taken on the line IX-IX of Fig. 2. Fig. 10 is a top plan view, with the cover removed, showing another form of railway switch operating apparatus embodying our invention. Fig. 11 is a vertical longitudinal sectional view of the apparatus shown in Fig. 10.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Figs. 1 and 2, the reference character I designates a casing which is adapted tov be secured to the ties or some other suitable foundation adjacent a railway track switch, and which is closed at its upper end by a removable cover 2. Journaled in the housing I adjacent one end thereofis a vertically extending switch actuating shaft 3, the lower end of which terminates in a crank i provided with a downwardly projecting crank pin 5. This crank and pin cooperate with suitable apparatus for actuating and looking a railway switch, which apparatus is not shown in the accompanying drawings, but which may, for example, be similar to the apparatus shown in Letters Patent of the United States No. 1,293,290, granted to William Zabel, on February 4, 1919, for Railway trafiic controlling apparatus. In the said patent, the crank 55 and pin 58 correspond respectively to the crank 4 and pin 5 in the; present disclosure.

The switch actuating shaft 3 is operatively connected, through. the medium of a train of gears and a combined clutch and brake mechanism A, with an electric motor M whichis secured to the casing l at the right-hand end of the casing. The train of gears forms no part of our present invention, and as here shown comprises a spur gear 1 keyed to the switch actuating shaft 3 and meshing with a spur gear 8 keyed to a jackshaft 9. The jackshaft 9 has fixed thereto a spur gear l2 which meshes with a spur gear I3. The spur gear l3, in turn, is secured to a second jackshaft I4 which latter shaft has attached thereto a spur gear H which meshes with a. spur pinion [8. The spur pinion I8 is rotatably and slidably mounted on a vertically disposed shaft l9 inv a manner which we q The reduction gear- The shaft i9 is journaled' at its lower end in a ball bearing 23 mounted in a bearing recess 24 formed in the lower part of the casing l, and at its upper end in a ball bearing 25 mounted in a bearing sleeve 26. The bearing sleeve 26. is adjustably screwed into a screw threaded hole 21 formed in a bearing plate 28 in such manner that the vertical position of the bearing 25 may be varied by screwing the bearing sleeve in one direction or the other in the hole 21, and formed on the upper end of the sleeve is a hexagonal flange or wrench grip 29 whichfacilitates adjusting the sleeve. The flange 29' also cooperates with suitable means which we will describe next for locking the bearing sleeve in an adjusted position. The bearing plate 28 is secured to the casing l by suitable bolts in an obvious manner,

the bearing sleeve, and the studs 3! are each provided adjacent their heads with enlarged shank portions which will enter the slots only at the enlarged portions of the slots. The parts areso proportioned that, when the enlarged shank portions of the studs are in the enlarged portions of the slots, the locking strap 30 will be held in a position in which an upturned end 34 formed on the strap will snugly engage the sleeve 26 at one of the hexagonal sides of the flange 29 in such manner that rotation of the sleeve is prevented, but that, when the studs are unscrewed to the positions in which their enlarged shank portions are withdrawn from the enlarged portions of the slots, the locking strap may be moved away from the bearing sleeve far enough to permit free rotation of the sleeve.

The spur pinion I8 is not mounted directly on the shaft 19, but is spaced from the shaft by a bushing 35 and by a cam follower 35 which forms part of the combined brake and clutch mechanism A. The bushing 35 and cam follower 35 are each free to both rotate and slide longitudinally on the shaft I9, and each extends into the hub of the pinion l8 with sufficient clearance so that the pinion is also free to both rotate and slide longitudinally with respect to the shaft 59. Surrounding the shaft it between the bushing 35 and-the cam follower 36 is a compress-ed coil spring 31 which constantly biases the pinion I8 to a lowermost position on the shaft l9 in a manner, and for a purpose which will be made clear hereinafter.

An annular flange 38 is formed on the hub of the pinion R8 at its lower end, and resting on top of flange 38 is a brake ring 45 which is locked against rotation relative to flange 38 by the head of one or more screws 39 (see Fig. 4). Each screw 39 passes through a clearance hole 4i provided in the brake ring, and is screwed into a depending cylindrical shoulder 42 which is formed on the flange 38 at its outer edge. As best seen in Fig. 4, the holes 4| in the brake ring 45 are equally spaced about the circumference of a circle whose center coincides with the axis of the shaft I9, and it will be apparent, therefore, that the brake ring 40 can be locked relative to the flange 38 in any one of a plurality of angular positions, each spaced apart a distance which is equal to the distance between each two adjacent holes 4!. The reason for locking the brake ring relative to the flange 38 in the manner just described will be made clear presently. The brake ring 45 cooperates with a friction ring 43 to form a brake 4043. The friction ring 43 is secured to a support 44 which is fastened to the side wall of the casing l.

A cup-shaped clutch housing 45 is screwed at its upper end into a depending cylindrical flange 46 which is formed on the brake ring 45 in concentric relation to the shoulder 42, and provided on the inside of this housing are a plurality of vertically disposed ribs or splines 41 which extend loosely into vertical grooves 48 formed in the shoulder 42, whereby rotation of the brake ring 4|] relative to the pinion it will cause vertical movement of the clutch housing 45 relative to the pinion. Pinned to the cam follower 36 within the housing 45 is a clutch sleeve 49 having formed .thereon an integral'clutch plate 50. A clutch facing 5| is disposed above the clutch plate 50, and interposed between this clutch facing and the shoulder 42 is a pressure plate 52. The pressure plate 52 is free to both rotate and move vertically with respect to the clutch sleeve 49, and isalso free to move vertically with respect to the clutch housing 45, but is prevented from rotating with respect to the clutch housing 45 by means of grooves 53 (see Fig. 9) which loosely receive the splines 47 on the clutch housing. A

clutch facing 54 is also disposed below the clutch plate 50, and this latter clutch facing cooperates with a pressure plate 55 which is similar to the pressure plate 52. The pressure plates and clutch facings are pressed together by two concentric compression springs 55 and 5'! which are interposed between the pressure plate 55 and the bottom of the housing 45. The amount of com pression of the springs 56 and El may be varied by varying the angular position of the brake ring 40 relative to the pinion H5, in a manner which will be explained hereinafter, thereby permitting the force required to slip the clutch to be readily varied.

As best seen in Figs. 2 and 3, the upper end of the clutch sleeve 49 is provided with a semicylindrical projection 43 which cooperates with a spring 59 to limit the amount that the clutch can slip. As here shown, the spring 59 is in the form of a split ring having enlarged ends 59 and 53 The outer portions of the ends 59 and 59* project into an arcuate recess 5!! formed in the shoulder 42, and cooperates with the shoulder 42 at the sides 65 and 65 of the recess, while the inner portions of the enlarged ends 59 and 59 project into the path of the semi-cylindrical projection 49 and cooperate with the sides 58 and 58 of this projection.

The lower end of the clutch sleeve 49 is provided with depending diametrically opposite lugs 49 and 49 which extend into diametrically opposite arcuate slots 25 and 25 machined in the hub of the bevel gear 25, as shown in Figs. and 6. The angular lengths ofv the slots 20 and 20 are approximately twice the angular lengths of the lugs 49 and 49, and it will be apparent, therefore, that the bevel gear 25 is free to rotate through a limited angle in either direction with respect to clutch sleeve 45, but that, after the bevel gear 25 has been rotated through this limited angle, any further rotation of the bevel gear will cause corresponding rotation of the clutch sleeve.

The cam follower 36 is provided at its lower end with tapered depending diametrically oppoportioned that, when the parts occupy their normal positions in which they are shown in the drawings, a limited amount of vertical clearance will exist between the cam follower and the brakereleasing cam, and between the lugs 39 and the associated cam slots ti as well as between the lower end of the clutch sleeve 45 and the upper end of the hub of the bevel gear 28.

The operation of the apparatus as a whole is as follows: When motor M is deenergized, clutch spring 3? acts through the medium of cam follower 36, clutch sleeve 49, clutch plate 55, clutch facing 54, pressure plate 55, springs 56 and 51, and clutch housing 45 to exert a downward force on the brake ring 45 which causes the brake ring to frictionally engage the friction ring 43, and

since the brake ring is fastened to the pinion l8 which, in turn, is operatively connected with the switch actuating shaft 3 through the medium of the gear train, it follows that under these conditions, the switch actuating shaft and the associated gearing are braked against rotation which otherwise might result because of vibration.

When, however, motor M becomes energized, the motor torque will be transmitted to cam 6! through bevel gears 2| and 28, and this torque will cause cam slots fil to cooperate with the lugs 39 on the cam follower 35 in such manner that the cam follower will be forced upwardly on the shaft l9. This upward movement of the cam follower, in turn, will act through the clutch sleeve 49, clutch plate 5!], clutch facing 5|, pres sure plate 52, and shoulder 42 to move the whole brake and clutch assembly upwardly on the shaft IE to a position in which the brake ring 40 is out of engagement with the friction ring 43, thus automatically releasing the brake. so proportioned that, as soon as the cam follower 36 has been moved vertically by the cam ii through a sufncient distance to properly release the brake, the depending lugs de and G9 on the cam follower 49 will rotate into engagement with the hub of the bevel gear 29 at one end or the other of the slots 26 and 26, respective-1y, depending upon the direction of rotation of the motor, and it will be apparent, therefore, that any torque which is transmitted to the clutch sleeve in excess of that necessary to release the brake will be transmitted directly to .the sleeve by the gear 26 through the medium of the lugs 19 and 49, thus providing a positive drive of the clutch sleeve. It will also be apparent that, as long as the motor continues to exert a torque, the brake will remain released. The torque which is transmitted to the clutch sleeve 49 is transmitted from the clutch sleeve to the pinion l8. and hence to the switch actuating shaft 3, through the medium of the slip clutch, and the springs 56 and 51 are so adjusted that under normal operating conditions no slipping of the clutch will take place except at the ends of. the switch stroke. The parts'are further so proportioned that the slipping which does take place at the ends of the switch stroke will be sufficient to prevent damage to the rotating parts due to the inertia of these parts, although the parts may have sufiicient inertia to cause the upstanding projection 4% on the upper end of the clutch sleeve 49 to move into engagement with the enlarged ends 5% or 59 of the clutch limiting spring 58. If, however, the load on the motor becomes excessive for any reason, due for example to the switch being unusually stiff or becoming stalled in an intermediate position, the slip clutch will slip sufficiently to permit the projeotion 39 to move into engagement with one enlarged end or the other of the clutch limiting spring 59 depending upon the direction of rotation of the motor. When this happens, the clutch limiting spring will become compressed in an obvious manner, and as a result, a part of the mo tor torque will then be transmitted to the switch actuating shaft through this spring. This increased torque will, of course, cause the motor current to increase, and if the overload continues for too long a time the increased current will cause the usual protective device which is provided for the purpose of preventing damage to the motor to operate and deenergize the motor. When the motor becomes deenergized in this manner, any energy which is stored in the clutch slip limiting spring 59 as the result of shock at the end of, or elsewhere in the stroke of the switch, will be snubbed against rapid rebound by the friction of the clutch, and will not, therefore,

The parts are operate to rapidly rotate the motor armature in the reverse direction. Furthermore, when the motor becomes deenergized, the energy of spring 37 and the weight of the clutch and brake assem bly will exert a downward force on the cam fol lower 36, which force will act through the medium of the cam El to drive the bevel gear 20, bevel pinion 2i and the motor armature 22 in the reverse direction through a sufficient angle to permit the brake ring 40 to engage the iriction ring 43 and hold the gear train and switch-actuating shaft 3 against movement. When the switch has been moved to either end of its stroke by the motor, the motor will, of course, become automatically deenergized through the medium of suitable control circuits in the usual and well known manner. i

As is well understood, the torque at which the slip clutch will slip depends upon the compression of the springs 55 and 51, and as was previously pointed out this compression may be varied by rotating the brake ring lil relative to the pinion 8 to cause vertical movement of the clutch housing Q5. To permit this adjustment to be conveniently made, we provide an adjusting key 62 which is shown in dot and dash lines in Fig. 2. As will be apparent from an inspection of Fig. 2, this key in the form here shown comprises a circular rod provided at its upper end with a handle 62 and fitted adjacent its lower end'with a gear 63. When it is desired to make an adjustment, the lower end of the key 62 is inserted into one of the holes ll in the brake ring 40, the parts being so proportioned that when the lower end of the key is in one of the holes in the brake ring,

the gear 63 will mesh with the pinion I8. The screw 39 is next removed from the brake ring, and the key 62 is then rotated, thus causing relative rotation of the brake ring and pinion l8, and hence causing vertical movement of the clutch housing 45 relative to the pinion 53. As soon as the desired adjustment has been made, the brake ring is again locked against rotation relative to flange 38 by means of the screw 39, and the key 62 is then removed from the switch operating apparatus.

The braking force exerted by the brake 40-43 depends upon the compression of the spring 37, and the compression of the spring 3? may be varied by varying the vertical position of the bearing sleeve relative to the bearing plate 23, as will readily be understood from an inspection of Fig. 2.

Under some conditions it is desirable to be able to operate the switch operating mechanism manua ly. For this purpose, the upper end 59 of the shaft i9 is made square to receive a hand crank not shown), and the cover 2 of the casing is provided with an opening 2 which is closed by an auxiliary cover 2 to enable the crank to be readily placed on the shaft. Rotation of the shaft H! by the hand crank will rotate bevel gear 20, and the resultant operation of the switch-actuating shaft'will be the same as when the gear 20 is operated by the motor through the medium of the pinion 2i.

It is obvious that cam 61 and cam follower 36 must be so designed as to have durable wearing surfaces which will permit the parts to slide freely upon each other. To provide the necessary durable wearing surfaces, these parts are preferably case hardened or made of material of special wearing quality.

It should-be pointed out that, While in the drawings the clutch limiting springs 59 is shown as a single ring open at one side, the clutch limiting spring may be constructed in the form of a coil, the ends of which are designed similar to the ends of the spring 5%, so that this spring will wind up and drive in either direction.

One advantage of a combined clutch and brake mechanism constructed in the manner described is that it occupies only a little more space than is required for an ordinary friction clutch or resilient drive.

Another advantage of the combined clutch and brake mechanism embodying our invention is that the use of a slip clutch combined with a limiting spring in the manner described provides a means by which the torque exerted on the switchactuating shaft in the event of an overload increases after a limited amount of slippage has taken place rather than decreases, as is the case with ordinary friction clutches. The advantage of this feature is that the motor current increases instead of decreases, thus insuring the quick and positive operation of the usual overload devices which are provided to protect the motor.

Referring now to Figs. 10 and 1] as here shown, spur gear l which drives the switch-actuating shaft 3 is operatively connected, through the medium of a cluster gear '58 keyed to a jackshaft H journaled in bearings '12 and i3, with a spur gear 15 keyed to a vertically disposed shaft 78. The shaft I6 is journaled in bearings 11 and I8, and has loosely mounted thereon above the spur gear '25 a sleeve is. A combination spur and bevel gear is keyed to the lower end of the sleeve 19, and this gear meshes with the bevel pinion 2| on the armature shaft 22 of motor M, and also with a spur gear 81 keyed to the lower end of a shaft 82. The shaft 82 is journaled in a suitable bearing 83 and hasits upper end squared for the reception of a hand crank by means of which the apparatus may at times be manually operated in manner which will be described more fully hereinafter. A substantially circular bearing plate 8 is mounted in a suitable guideway 85 formed in the casing I. in such manner that this plate is free to rotate through a limited angle, and pivotally attached to diametrically opposite ears 86 and 8! formed on. this plate are two spring guides 88 and 89, respectively. The free ends of the spring guides 88 and 89 are slidably supported in holes 99 and 9! formed in lugs 92 and 93 provided on a bracket 94, and mounted on each guide between the associated lug e2 or 93 and the associated ear 86 or Bl is a compressed coil spring 95, which springs bias-the bearing plate 84 to one angular position relative to the casing I in a manner which will be obvious from an inspection of the drawings.

A plurality of studs 96 project upwardly from the bearing plate 84 and are rigidly connected together at their upper ends by an annular plate 9'5 which surrounds the sleeve 79 with considerable clearance. The studs are all equally distant from the axis of the shaft 76, and journaled on each stud is a pinion 98. Each pinion 98 meshes with a pinion 99 journaled on the sleeve 19 above the gear 80, and also with integral gear teeth Hid formed on a gear wheel ill!) which is keyed to the upper end of the shaft 16 directly above the upper end of the sleeve 19.

An enlarged portion 79 is formed on the upper end of the sleeve E9, and projecting downwardly from this enlarged portion are depending diametrically opposite tapered lugs "i9 which extend into, and cooperate with, cam slots 99* formed in the hub of the pinion 99.

A brake disk MI is secured to the pinion 99 at its lower end, and interposed between the underside of this disk and the upper side oi the combination gear Bil is a compressed coil spring I02 which constantly biases the brake disk HM and the pinion 99 to an upper position on the sleeve 19, in which position a friction ring H33 secured to the brake disk frictionally engages the underside of the bearing plate 8d.

The operation of the apparatus shown in Figs. 10 and 11 is as follows: When motor M is deenergized, the spring Q92 holds the pinion 99 and brake disk NH in the vertical position on the sleeve 19 in which the friction ring Hi3 engages the underside of the bearing plate 34 with sufficient force to prevent rotation of the pinion 99, and under these conditions the shaft i6 is braked against rotation in an obvious manner, thus securely holding the gear train and switchactuating switch 3 against rotation due to vibration and the like.

When, however, motor M becomes energized, a torque is then exerted on sleeve i9 through the medium of gears 2i and and this torque acts through the lugs 19* and cam slots 99 in the hub of pinion 99 to force the pinion and brake disk ml downwardly on the sleeve 79 in opposition to the bias of spring 102, to a position in which the hub of pinion 99 engages the hub of gear 88. In this position of the parts, the friction disk N33 is out of engagement with the bearing plate 34, and the pinion 99 is therefore free to rotate relative to the bearing plate in response to the torque which is transmitted to the pinion through the medium of the lugs 19 and cam slots 99*. Rotation of the pinion it causes the pinions 98 to rotate and, inasmuch as the bearing plate 34 is held substantially fixed by the springs $5, the rotation of the pinions 95 causes the gear set, and hence the shaft '55, to rotate. The rotation of the shaft 16, in turn, is transmitted to the switch actuating shaft 3 in an obvious manner. When the switch has been rotated to the end of its stroke by the switch operating apparatus, or in the event that the switch is stopped in an intermediate position by an obstruction, the sudden increase in load on the motor will cause the bearing plate 84 to rotate in one direction or the other and compress one or the other of the springs 95 depending upon the direction of rotation of the motor, thus cushioning the shock due to the inertia of the parts.

When the switch reaches the end of its stroke,

motor M will, of course, become deenergized due to the usual control apparatus, and since a torque is then no longer exerted on the sleeve '19, the spring I532 then will move the brake disk [ill and pin 99 upwardly on the sleeve 79 to the position shown in the drawings, thus again ho1ding the gearing against motion due to vibration and the like. All parts will then be restored to the positions in which they are shown in the drawings.

When it is desired to operate the switch operating apparatus by hand, the shaft 82 is rotated by means of a hand crank. This rotation rotates the gear 88 in the same manner that this gear is rotated by the motor M, and the operation of the apparatus under these conditions is similar to that previously described and need not therefore be repeated.

Although we have herein shown and described only two forms of railway switch operating apparatus embodying our invention, it is under stood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. Railway switch operating apparatus comprising a rotatable shaft, a pinion biased to one longitudinal position on said shaft, bralnng means secured to said pinion and effective when said pinion occupies said one position for preventing rotation of said pinion, power means for driving said shaft connected with said shaft, cam mechanism on said shaft effective when a torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said brake mechanism is released, and means responsive to rotation of said shaft for driving said pinion.

2. Railway switch operating apparatus comprising a rotatable shaft, a pinion loosely mounted on said shaft in such manner that said pinion is both free to rotate and slide longitudinally along said shaft, biasing means for biasing said pinion to one longitudinal position on said shaft, braking means secured to said pinion and effective when said pinion occupies said one longitudinal position on said shaft for preventing rotation of said pinion, slip clutch mechanism for operatively connecting said pinion with said shaft, and means effective when a torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said braking means is ineffective to prevent operation of said shaft.

3. Railway switch operating apparatus comprising a rotatable shaft, a pinion loosely mounted on said shaft in such manner that said pinion is both free to rotate and slide longitudinally along said shaft, biasing means for biasing said pinion to one longitudinal position on said shaft, braking means secured to said pinion and effective when said pinion occupies said one longitudinal position on said shaft for preventing rotation of said pinion, means for operatively connecting said pinion with said shaft, and means effective when a torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said braking means is ineffective to prevent operation of said shaft.

4. Railway switch operating apparatus comprising a rotatable shaft, a pinion loosely mounted on said shaft in such manner that said pinion is both free to rotate and slide longitudinally along said shaft, biasing means for biasing said pinion to one longitudinal position on said shaft, braking means secured to said pinion and effective when said pinion occupies said one longitudinal position on said shaft for preventing rotation of said pinion, slip clutch mechanism for operatively connecting said pinion with said shaft, means for yieldably limiting the amount of slipping of said slip clutch mechanism, and means effective when a torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said braking means is ineffective to prevent operation of said shaft.

5. Railway switch operating apparatus comprising a rotatable shaft, a pinion loosely mounted on said shaft in such manner that said pinion is both free to rotate and slide longitudinally: along said shaft, biasing means for biasing said pinion to one longitudinal position on said shaft, braking means secured to said pinion andeifective when said pinion occupies said one longitudinal position on said shaft for preventing rotation of said pinion, slip clutch mechanism for operatively connecting said pinion with said shaft, a clutch slip limiting spring cooperating with said slip clutch mechanism, and means effective when a torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said braking means is ineffective to prevent operation of said shaft.

6. Railway switch operating apparatus comprising a rotatable shaft, a pinion loosely mounted on said shaft in such manner that said pinion is both free to rotate and slide longitudinally along said shaft, biasing means for biasing said pinion to one longitudinal position on said shaft, braking means secured to said pinion and effective when said pinion occupies said one longitudinal position on said shaft for preventing rotation of said pinion, slip clutch mechanism for operatively connecting saidpinion with said shaft, means for yieldably limiting the amount of slipping of said slip clutch mechanism, means effective when a. torque is exerted on said shaft for moving said pinion in opposition to its bias to a position in which said braking means is ineffective to prevent operation of said shaft, and a switch actuating shaft operatively connected with said rotatable shaft.

'7. Railway switch operating apparatus including a rotatable shaft, means for at times rotating said shaft, a cam secured to said shaft, a member biased to one position on said shaft and cooperating with said cam in such manner that when a torque is exerted on said shaft said member will be'mo-ved to another longitudinal position on said shaft, braking mechanism operatively connected with said member and effective when and only when said member occupies the position to which it is biased for preventing rotation of said member, means for operatively connecting said member with said shaft in such manner that only a limited amount of angular movement of said member relative to said shaft is permitted, and a switch actuating shaft operatively connected with said member.

8. Railway switch operating apparatus including a rotatable shaft, a gear keyed to said shaft and provided in the hub thereof with diametrically opposite slots, means for driving said gear, a cam on said shaft provided with tapered cam slots and with lugs which engage the hub of said gear at said slots, a cam follower loosely mounted on said shaft above said cam and provided with depending tapered lugs, a bushing on said shaft, a compressed spring between said bushing and said cam follower arranged to bias said cam follower to a longitudinal position on said shaft in which the associated lugs enter and cooperate with the slots in said cam, a pinion loosely mounted on said bushing and said cam follower, a flange on said pinion provided with a depending annular shoulder, said shoulder being provided in its outer surface with a plurality of vertical grooves, a brake ring secured to said flange in such manner that the angular position of said ring with respect to said flange may be varied, a depending flange formed on said brake ring in concentric relation to said annular shoulder, a cup-shaped clutch housing screwed into the flange on said brake ring and provided with vertical ribs which cooperate with the grooves in said shoulder, .a clutch sleeve secured to said cam follower and provided with a clutch plate, clutch facings disposed on opposite sides of said clutch plate, a first pressure plate disposed between the one clutch facing and said shoulder and provided with grooves which loosely receive the ribs on said housing, a second pressure plate cooperating with the remaining clutch facing and provided with grooves which receive the ribs on said housing, both said pressure plates being free to move longitudinally along said clutch sleeve and to rotate relative to said clutch plate, a compressed spring interposed between said second pressure plate and the bottom of said housing, and a switch operating shaft operatively connected with said pinion. 1

9. Railway switch operating apparatus includ ing a rotatable shaft, a gear keyed to said shaft and provided in the hub thereof with diametrically opposite slots, means for driving said gear, a cam on said shaft provided with tapered cam slots and with lugs which engage the hub of said gear at said slots, a cam follower loosely mounted on said shaft above said cam and provided with depending tapered lugs, a bushing on said shaft, a compressed spring between said bushing and said cam. follower arranged to bias said cam follower to a longitudinal position on said shaft in which the associated lugs enter and cooperate with the slots in said cam, a pinion loosely mounted on said sleeve and said cam follower, a flange on said pinion provided with a depending annular shoulder, said shoulder being provided in its outer surface with a plurality of vertical grooves, a brake ring secured to said flange in such manner that the angular position of said ring with respect to said flange may be varied, a depending flange formed on said brake ring in concentric relation to said annular shoulder, a cup-shaped clutch housing screwed into the flange on said brake ring and provided with vertical ribs which cooperate with the grooves in said shoulder, a clutch sleeve secured to said cam follower and provided with a clutch plate, clutch facings disposed on opposite sides of said clutch plate, a first pressure plate disposed between the one clutch facing and said shoulder and provided with grooves which loosely receive the ribs on said housing, a second pressure plate cooperating with the remaining clutch facing and provided with grooves which loosely receive the ribs on said housing, both said pressure plates being free to move longitudinally along said clutch sleeve and to rotate relative to said clutch plate, a compressed spring interposed between said second pressure plate and the bottom of said housing, a switch operating shaft operatively connected with said pinion, an arcuate recess formed in said shoulder, a semicircular projection formed on the upper end of said clutch sleeve, and a spring surrounding said semicircular projection to limit the amount of slipping of said clutch, said spring being in the form of an open ring and being provided with enlarged ends which enter said recess and which cooperate with said projection.

10. Railway switch operating apparatus including a rotatable shaft, a gear keyed to said shaft and provided in the hub thereof with diametrically opposite slots, means for driving said gear, a cam on said shaft provided with tapered cam slots and with lugs which engage the hub of said gear at said slots, a cam follower loosely mounted on said shaft above said cam and provided with depending tapered lugs, a bushing on said shaft, a compressed spring between said bushing and said cam follower arrangedto bias said cam follower to a longitudinal position on said shaft in which the associated lugs enter and cooperate with the slots in said cam, a pinion loosely mounted on said sleeve and said cam follower, a flange on said pinion provided with a depending annular shoulder, said shoulder being provided in its outer surface with a plurality of vertical grooves, a brake ring secured to said flange in such manner that the angular position of said ring with respect to said flange may be varied, a depending flange formed on said brake ring in concentric relation to said annular shoulder, a cup-shaped clutch housing screwed into the fiange on said brake ring and provided with vertical ribs which cooperate with the grooves in said shoulder, a clutch sleeve secured to said cam follower and provided with a clutch plate, clutch facings disposed on opposite sides of said clutch plate, a first pressure plate disposed between the one clutch facing and said shoulder and provided with grooves which loosely receive the ribs on said housing, a second pressure plate cooperating with the remaining clutch facing and provided with grooves which loosely receive the ribs on said housing, both said pressure plates bein free to move longitudinally along said clutch sleeve and to rotate relative to said clutch plate, a compressed spring interposed between said second pressure plate and the bottom of said housing, a switch operating shaft operatively connected with said pinion, and depending lugs formed on the lower end of said clutch sleeve and extending into the slots in said hub in such manner that only a limited amount of rotation of said clutch sleeve relative to said gear is permitted.

11. Railway switch operating apparatus com- 1 rising a casing, a first shaft journaled in said casing, a first gear wheel secured to said first shaft, a switch actuating shaft operatively connected with said first gear wheel, a sleeve journaled on said first shaft, a second gear wheel secured to said sleeve, means for driving said second gear wheel, a first pinion journaled on said sleeve above said second gear wheel, a bearing plate surrounding said first shaft with clearance between said pinion and said gear wheel and mounted in said casing in such manner that said plate is free to rotate through a limited angle, spring means for biasing said plate to one angular position in said casing, a plurality of studs secured to said bearing plate about the circumference of a circle whose center coincides with the axis of said first shaft, a plurality of pinions one journaled on each stud and each meshing with said first pinion, a third gear wheel secured to said first shaft above said sleeve and provided with internal gear teeth which mesh with each pinion of said plurality of pinions, a brake disk secured to the lower end of said first pinion and provided with a friction ring which cooperates with the underside of said bearing plate, a spring interposed between said brake disk and said second gear wheel and effective for biasing said first pinion to a position in which said friction ring frictionally engages said bearing plate, diametrically opposite tapered cam slots formed in the upper end of the hub of said first pinion, and depending tapered lugs formed on said sleeve and cooperating with said cam slots in such manner that when said second gear wheel is rotated said lugs will cooperate with said cam slots to move said pinion to a position in which said friction ring is out of engagement with said bearing plate.

12. Railway switch operating apparatus comprising a casing, a first shaft journaled in said casing, a first gear wheel secured to said first shaft, a switch actuating shaft operatively connected with said first gear wheel, a sleeve journaled on said first shaft, a second gear wheel secured to said sleeve, power means and manually operable means for driving said second gear wheel both operatively connected with said second gear wheel, a first pinion journaled on said sleeve above said second gear wheel, a bearing plate surrounding said shaft with clearance between said pinion and said gear wheel and mounted in said casing in such manner that said plate is free to rotate through a limited angle, spring means for biasing said plate to one angular position in said casing, a plurality of studs secured to said bearring which cooperates with the under side of said bearing plate, a spring interposed between said brake disk and said second gear wheel and effective for biasing said first pinion to a position in which said friction ring frictionally engages said bearing plate, diametrically opposite tapered cam slots formed in the upper end of the hub of said first pinion, and depending tapered lugs formed on said sleeve and cooperating with said cam slots in such manner that when said second gear wheel is rotated said lugs will cooperate with said cam slots to move said pinion to a position in which said friction ring is out of engagement with said bearing plate. I

13. Railway switch operating apparatus comprising a casing, a shaft journaled in said casing, a sleeve journaled on said shaft, a first gear wheel secured to said sleeve, means for driving said first gear wheel, a first pinion rotatably and slidably mounted on said sleeve, a bearing plate surrounding said shaft with clearance and mounted in said casing in such manner that said plate is free to rotate through a limited angle relative to said casing, means for biasing said bearing plate to one angular position relative to said casing, a second gear wheel secured to said shaft and provided with internal gear teeth, a plurality of pinions mounted on said bearing plate and each meshing with the teeth on said first pinion and with the teeth on said second gear wheel, a brake disk secured to said first pinion and provided on one side thereof with a friction ring, means for biasing said first pinion to a longitudinal position on said sleeve in which said friction ring frictionally engages said bearing plate, means on said sleeve cooperating with means on. said first pinion for moving said first pinion in opposition to its bias to a position in which said friction ring is out of engagement with said bearing plate whenever a torque is exerted on said sleeve, and switch operating means operatively connected with said shaft.

14. Railway switch operating apparatus comprising a casing, a first shaft journaled in said casing, a sleeve loosely mounted on said first shaft, a first gear wheel secured to said sleeve, power means for driving said first gear wheel operatively connected with said first gear wheel, a second shaft journaled' in said casing, means on one end of said second shaft for the reception of a hand crank, a second gear wheel secured to said second shaft and meshing with said first gear wheel, a first pinion rotatably and slidably mounted on said sleeve, a bearing plate surrounding said shaft with clearance and mounted in said casing in such manner that said bearing plate is free to rotate through a limited angle relative to said casing, means for biasing said bearing plate to one angular position relative to said casing, a third gear wheel secured to said shaft and provided with internal gear teeth, a plurality of pinions mounted on said bearing plate and each meshing with the teeth on said third gear wheel and with the teeth on said first pinion, a brake disk secured to said first pinion and provided on one side thereof with a friction ring, means for biasing said first pinion to a longitudinal position on said sleeve in which said friction ring frictionally engages said bearing plate, means on said sleeve cooperating with means on said first pinion for moving said first pinion in opposition to its bias to a position in which said friction ring is out of engagement with said bearing plate whenever a torque is exerted on said sleeve, and

switch operating means operatively connected screw threaded hole and at the other end with a polygonal flange which forms a wrench grip to facilitate turning said sleeve to move it to different adjusted positions relative to said bearing plate, a locking strap provided with an upstanding end, and means for securing said locking strap to said bearing plate in such manner that when said securing means are tightened said upturned end will engage one of the sides of the polygonal flange of said sleeve and prevent rotation of the sleeve but that when said securing means are loosened said locking strap may be moved to a position in which free rotation of said sleeve is permitted.

16. In combination, a bearing plate having a screw threaded hole extending therethrough, a bearing sleeve provided at one end with external screw threads which are screwed through said screw threaded hole and at the other end with a polygonal flange which forms a wrench grip to facilitate turning said sleeve to move it to different adjusted positions relative to said bearing plate, a locking strap provided with an upstanding end and with two elongated holes each cf which is enlarged at the ends which are farthest away from said upstanding end, and two 7 screws one extending through each hole in said strap and each screwed at its lower end into said bearing plate, each said screw being provided adjacent its head with an enlarged shank portion which will enter the associated slot only at the enlarged end of the slot, the parts being so proportioned that when the enlarged shank portions of the studs are in the enlarged portions of the associated slots the locking strap will be held in a position in which the upstanding end will engage one of the sides of said polygonal flange and will prevent rotation of said sleeve but that when the enlarged shank portions of the studs are Withdrawn from the enlarged portions of the associated slots the locking strap may be moved away from the bearing sleeve far enough to permit free rotation of the sleeve.

1'7. Railway switch operating apparatus comprising a casing, a bearing plate secured to said casing in the upper part of the casing, said bear- 75 ing plate having a screw threaded hole extending therethrough, a bearing sleeve provided at one end with external screw threads which are screwed through said screw threaded hole and at the other end with a polygonal flange which forms a wrench grip to facilitate turning said sleeve to move it to different adjusted positions relative to said bearing plate, a locking strap provided with an upstanding end, means for securing said locking strap to said bearing plate in such manner that when said securing means are tightened said upturned end will engage one of the sides of the polygonal flange of said sleeve and prevent rotation of the sleeve but that when said securing means are loosened said locking strap may be moved to a position in which free ei'ation of said sleeve is permitted, a first bearing mounted in said bearing sleeve, a rotatable shaft journaled at one end in said first bearing and at the other end in a bearing provided in said casing, brake mechanism on said shaft biased to a braking position by a compression spring in such manner that the compression of said spring depends upon the position of said bearing sleeve 1' *lative to said bearing plate, said brake mecha n being effective when in its braking posi- )1 for preventing operation of said shaft, means for actuating said shaft operatively connected with the shaft, and means effective when a torque is exerted on said shaft by said actuating means for moving said brake mechanism away from its braking position in opposition to the bias of s id spring.

18. Railway switch operating apparatus comprising an adjustable bearing sleeve, a bearing mounted in said bearing sleeve, a rotatable shaft i urnaled at one end in said bearing, brake mechsrn. operatively connected with the shaft, said brake mechanism'being biased to a braking position by a compression spring the compression of which depends upon the adjustment of said bearg sleeve, means for actuating said shaft opera- 'mely connected with the shaft, and means effective when a torque is exerted on said shaft by said actuating means for moving said brake mechanism away from its braking position in opposition to the bias of said spring.

19. Railway switch operating apparatus comprising a casing, a bearing plate mounted in said casing and provided with a screw threaded hole, a bearing sleeve adjust-ably screwed into said hole, means for looking said hearing sleeve in an ad,tisted position with respect to said plate, a sha t rotatably mounted at one end in a bearing mounted in said bearing sleeve and at the other ad in a bearing mounted in a bearing recess v ded in said casing, slip clutch mechanism movable longitudinally along said shaft, a fixed friction ring surrounding said shaft, a brake ring secured to said slip clutch mechanism, a compressed coil spring biasing said slip clutch mechanism to a longitudinal position on said shaft in which said brake ring frictionally engages said friction ring in such manner that the com- ,rression of said spring may be varied by varying the adjustment of said bearing sleeve relative to said bearing plate, means for driving said shaft. ans effective when a torque is exerted on said by said driving means for moving said slip 91'- tch mechanism longitudinally along the shaft a position in which said brake ring is out of engagement with said friction ring, and switch actuating means operatively connected with said shaft through said slip clutch mechanism.

WILLIAM C. MCWHIRTER. EDWIN G. LITTLE. 

